Fan / Temperature Sender problem

[GSi]

I knew the car had a problem with the fan when I bought it so no surprise, but now I'm trying to figure out what it needs doing to sort it out.

The Fan fuse was blown, so I replaced that and the fan now comes on with ignition.  However, it runs all the time.

I had a poke around with the assistance of a couple of other local helpers and at the rear of the engine (2l zetec) there is a circular plug with two pins in it and a cable which appears to fit into the plug (with a pale blue connector on it).  This was disconnected.

When it is plugged back in, the fan doesn't come on with ignition.   However, when the car gets hot (over 100) it still doesn't kick in.

So my guesses:

1) the thermostat/sender is broken and doesn't trip the fan

2) the plug/cabling is knackered

Not sure if there are many more options, but where should I start to look next?

I have a meter, so can measure the current across the pins/plug if necessary, but I'm not sure what I'm looking for.

Rob.

[pete g]

shold be simple to sort

it a very easy circuit

switch in engine should just make when up to temp

fuse to switch  /switch to fan /fan to earth

unless there is a relay some where

short out the switch and the fan sould run  

[GSi]

Checked the wiring (shorting the pins runs the fan), so I guess the switch is the likely suspect.

Just waiting for it to cool down so I can have a look.

[Blatman]

It's worth fitting a relay in the fan circuit too, otherwise your next post will be asking why the engine doesn't switch off when the fan is running Plenty of folk have asked about that in the past...

[GSi]

 thanks for that..  I'll look into it (i.e get my sparky mate to have a look at it for me )